Networks such as the Internet are primarily designed for delivering static, non-real-time data to fixed clients such as desktop and laptop computers. In comparison, networks such as wireless networks face unique challenges because they need to provide services to clients with greater mobility that may be anywhere within any of the different regions of coverage.
In the case of streaming media services, these challenges are intensified due to the richness of the streamed media data. The volume of streamed media data to be delivered to each client is large and sensitive to delays. The streamed data need to be delivered without interruption and within certain time constraints while the client roams freely among the regions of coverage. Moreover, as the mobile client migrates from one region (cell) to another, the data source (e.g., a server or some other such content provider) and the data delivery path also need to change correspondingly so that the delivery of data to the client is maintained at a satisfactory level.
The challenges faced with streaming media services to mobile clients are further intensified when considering issues like system scalability, which extends service to a larger number of users, and quality-of-service and fault tolerance, which provide mobile users with continuous, uninterrupted streaming media sessions. Other considerations include the load on the data source, network conditions such as congestion along the data delivery path, and the loads at the various nodes (e.g., servers and routers) in the network.
In response to these challenges, a method was developed for distributing multimedia data to servers closest to regions in which high concentrations of interested clients are expected. This method is described in the co-pending, commonly-owned US Patent Application, . Ser. No. 09/895,650, filed Jul. 3, 2001, by J. G. Apostolopoulos et al., and entitled “Method for Assigning a Streaming Media Session to a Server in Fixed and Mobile Streaming Media Systems,” hereby incorporated by reference.
According to the referenced method, content (e.g., multimedia data) is placed at servers with anticipated high demand (“hot spots”). These hot spots are identified based on a variety of factors including user statistics. The hot spot evaluation can be repeated to update the list of hot spots as user statistics change.
Generally speaking, the referenced method accomplishes its objectives based on an evaluation of historical information. However, there may be instances not anticipated by the historical information. Accordingly, what is needed is a method and/or system that does not rely solely on historical information to guide the distribution of multimedia data to a mobile client. The present invention provides a novel solution to this need.